JSON-Based Multi-Link Field Architecture

This document summarizes a proposed architecture for storing and managing 0…N website links per record in Drupal, using a single text field containing JSON and a modal-based custom widget.

The goal is:

A clean edit form (one line only)
A modal to manage multiple links
Deterministic behavior (no handler surprises)
Easy rendering in Views and Twig
Reusable across all content types

1. Overview

Instead of using Drupal’s multi-value Link field (which clutters the edit form), a single text field is used to store all links in JSON format.

Each record stores its own JSON string. There is no global file.

Example JSON stored in the field:

[
  { "label": "Foo", "url": "https://foo.com" },
  { "label": "Bar", "url": "https://bar.com" }
]

2. Edit Form UX

The edit form shows only one line:

Website links: [ Manage links ]

Clicking the button opens a modal where the editor can:

Add a link
Edit a link
Remove a link
Reorder links

When the modal is saved, the JSON is written back into the field.

3. Storage Model

A single field (e.g., field_links_json) stores the JSON string.

Characteristics:

One JSON string per record
No shared storage
No extra entities required
Deterministic and simple

4. Rendering in Twig

Twig can decode and loop through the JSON:

{% set links = node.field_links_json.value|json_decode %}
<ul>
{% for link in links %}
  <li><a href="{{ link.url }}">{{ link.label }}</a></li>
{% endfor %}
</ul>

5. Rendering in Views

A small custom Views field handler is used.

Responsibilities:

Read the JSON string
Decode it
Render 0…N links as HTML or a render array

This keeps Views clean and avoids exposing raw JSON.

6. Reusability

This architecture works for:

All records in a content type
Any number of content types
Any custom entity type

The field and widget are generic and reusable.

7. Module Complexity Estimate

Approximate code size:

Field widget: 80–120 lines
Modal form: 100–150 lines
Views field handler: 60–80 lines
Module scaffolding: 20–40 lines

Total: ~260–390 lines of code.

8. Advantages

Clean edit form (one line only)
Deterministic behavior
No multi-value field clutter
No handler switching
Easy to render in Twig and Views
Successor-friendly and maintainable
Reusable across the entire system

9. Considerations

Links are not reusable across records (by design)
Requires a small custom module
JSON must be validated in the modal

10. Conclusion

This JSON-based approach provides a clean, predictable, and maintainable solution for managing multiple website links per record, without cluttering the edit form or relying on Drupal’s multi-value field behavior.